The present invention relates to veneer-slicers, and particularly to veneer-slicers that have adjustable cutting blades. More particularly, the invention relates to a veneer-slicer with remotely operable adjustable cutting blades, powered actuators for adjusting the cutting blades, and apparatus, remote from the veneer-slicer, to control the actuators.
Veneer-slicing machines are known in the art. See, for example, U.S. Pat. Nos. 793,306; 2,576,520; 3,441,069; and 4,601,317.
Typically, veneer-slicing machines include a carriage for supporting a pressure plate and cutting blade assembly. The carriage is movable in a horizontal plane toward and away from a log, or flitch, to be sliced. The pressure plate and cutting blade assembly includes a blade carrier that is pivotably mounted to the carriage for rotation about a pivot axis that lies parallel to the flitch. The cutting blade is attached to the blade carrier and positioned to present a predetermined angle of attack relative to the flitch to be sliced. The pressure plate is movable relative to the cutting blade to provide a gap between the pressure plate and the cutting blade through which the veneer sheet passes as it is sliced from the flitch.
A flitch support assembly for supporting the flitch moves vertically relative to the carriage and cutting blade. During each downward (or upward) stroke of the flitch, the cutting blade slices a veneer sheet from the flitch. As the flitch is sliced into veneer sheets, the cutting blade becomes dull. Eventually, if the blade becomes dull enough, the machine operator may rotate the cutting blade about the pivot axis to adjust the angle of attack to maintain an improved cutting edge presented to the flitch.
To facilitate adjusting the angle of attack, a pair of adjusting screws are coupled to the carriage and to the blade carrier. The adjusting screws are coupled to the blade carrier at each end of the blade carrier remote from the pivot axis. By turning the screws, the blade carrier is lifted relative to the carriage to rotate the blade carrier and cutting blade about the pivot axis. As the blade rotates about the pivot axis, the angle of attack of the blade changes relative to the flitch. The gap between the pressure plate and cutting blade does not change as the cutting blade is rotated.
Heretofore, an operator had to turn the adjusting screws manually to adjust the angle of attack, which meant that the machine had to be idle for at least as long as it took the worker to get the necessary tools, make the required adjustments, and then get clear of the machine. A blade angle adjusting mechanism that allows a machine operator, positioned remotely from the veneer-slicing machine, to adjust the angle of attack of the cutting blade quickly and accurately and with a minimum of down time on the machine would provide a substantial improvement over conventional manual blade angle adjusting mechanisms.
According to the present invention, a veneer-slicing apparatus comprises a reciprocating flitch table for moving a flitch to be sliced in a substantially vertical plane and a reciprocating carriage movable in a substantially horizontal plane. The reciprocation of the flitch table includes a slicing stroke and a return stroke, and the reciprocation of the carriage includes movement in a first direction toward the plane of reciprocation of the flitch table and movement in a second direction opposite to the first direction. A cutting blade is coupled to the carriage and is oriented to present a predetermined angle of attack relative to the flitch to slice a veneer sheet from the flitch during the slicing stroke of the flitch table.
In accordance with the invention, a remotely operable means for rotating the cutting blade can be operated to alter the angle of attack of the cutting blade relative to the flitch. The rotating means includes remotely controlled and powered positioning means for rotating the cutting blade relative to the flitch, and means, remote from the veneer-slicing apparatus, for controlling the positioning means.
In a preferred embodiment of the invention, the remotely controlled positioning means includes at least one electrohydraulic piston and cylinder, and a fluid source to deliver fluid under pressure, which is controlled to change the position of the piston and adjust the angle of attack of the cutting blade relative to the flitch. The controlling means includes a computer, at least one piston position sensor, at least one hydraulic flow control valve and an operator console electrically coupled to each other. The computer and operator console can be positioned remote from the veneer-slicer. The computer accepts a position indicating signal from the piston position sensor and a command signal from the operator console. The computer processes the signals and sends a control signal to the flow control valve to control the delivery of fluid to the electrohydraulic piston and cylinder to change the position of the piston according to the command signal. The computer also sends another signal to a display to indicate the position of the piston.
By providing at least one electrohydraulic piston and cylinder and control valve, computer, piston position sensor, and operator control console, the present invention provides a reliable improvement to slicing machines that allows an operator to adjust the angle of attack of the cutting blade remotely from the operator console. Thus, the operator no longer need stop the machine and manually turn an adjusting screw, and machine down time is minimized.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode as presently perceived.